October 20, 2014

View as List 7 Things to Know About #1

  • 7 Things to Know About #1

    In ancient times, doctors examined urine visually—sometimes even tasted it—to diagnose disease. Although this medical practice, called uroscopy, fell out of favor in recent centuries, urine can still provide some insight into a person’s state of health. Here is everything you’ve always wanted to know about urine—but were afraid to ask.

  • 1

    What is urine?

    It is liquid waste filtered from the blood and excreted by the kidneys. About 95 percent is water; the rest consists of byproducts of metabolism, such as urea, along with small amounts of excess salts, hormones, vitamins and other substances.

  • 2

    What makes it yellow?

    The color comes from a pigment called urochrome (from the breakdown of red blood cells) and ranges from pale yellow to amber. More concentrated urine is darker, an indication of dehydration. A good rule is to drink enough fluids to keep your urine almost colorless.

  • 3

    What causes color changes?

    Supplements, drugs and illness can turn urine surprising colors. For instance, excess riboflavin, a B vitamin, makes urine bright yellow. Phenazopyridine (such as Pyridium), for symptoms of bladder infections, turns it bright orange. Eating beets or blackberries may cause red urine, while rhubarb and some laxatives can turn it brown. If your urine is pink, red or brown for unknown reasons, see your doctor to rule out blood in the urine from, for example, an infection, kidney stone or, more rarely, bladder cancer. Brown urine may also be due to liver problems.

  • 4

    Why is urine sometimes cloudy?

    Cloudy urine is usually of no concern. It could be caused by normal secretions or by phosphate crystals that form if you’ve had a lot of milk or other high-phosphate foods. But if your urine is persistently cloudy or accompanied by other symptoms—such as burning upon urination, frequent urination or fever—it could be a sign of bacterial infection or other condition.

  • 5

    What gives urine its odor?

    Urea, ammonia and other chemicals excreted by the kidneys give urine an odor. If you are well hydrated and healthy, there should be little or no odor. Darker-yellow urine, because it is more concentrated, smells stronger. Penicillin gives urine a distinctive smell. So, too, does asparagus in many people (though some cannot smell it). Some medical conditions may also change urine’s odor. For example, diabetes can make it smell sweet.

  • 6

    What does a urine test reveal?

    A dipstick urinalysis checks for sugar (a possible sign of diabetes), protein (which can indicate kidney disease), white blood cells (possibly due to a urinary tract infection) and blood. It also tests specific gravity (that is, concentration) and pH (acidity/alkalinity) of the urine. In addition, urine tests can reveal many other things, including pregnancy and liver disease.

  • 7

    Does urine have healing properties?

    Urine has been ingested to treat heartburn, gout, flu, measles and diphtheria; rubbed into the chest for bronchial infections; gargled for throat infections; and applied to wounds. According to an article in the American Journal of Nephrology, substances in urine may inhibit microorganisms and have other effects. But there's no evidence that "urine therapy" has benefits. It’s a myth that applying urine to jellyfish stings can help, and it may cause remaining stingers to fire more. Drinking urine may cause nausea, vomiting, headache, palpitations, diarrhea and fever.